Modern electric vehicles generally allow two charging modes. A vehicle has a so-called on-board charging device for charging at a desired AC voltage or three-phase socket, said charging device controlling both the required conversion to direct current and a charging operation of a battery comprised by the vehicle. However, such an AC charging mode is extremely restricted in terms of charging speed on account of the connection power available, generally not more than 16 A or 32 A, and on account of an installation of the charging device with sufficient power. In modern electric vehicles, this results in charging times of several hours to be able to travel 100 km.
On account of the long charging times for AC charging, DC voltage charging, that is to say so-called DC charging, has been developed. In contrast to AC charging, in this case the vehicle does not have its own on-board charging device. Instead, a charging column or charging station outside the vehicle carries out the charging process and thus likewise forms current and voltage, as is necessary for charging the battery of the vehicle. During the charging process, DC charging lines that are to be provided are connected directly to poles of the battery, that is to say to the high-voltage battery of the vehicle. There is generally no DC isolation between the DC charging lines and the battery. Powers of DC charging stations are currently up to 50 kW. It is now desirable to achieve powers of up to 300 kW in order to surpass charging speeds of more than 20 km/min. Furthermore, a charging voltage of up to 1000 V is sought in order to achieve a corresponding charging speed. Recharging during travel is thus intended to be brought to orders of magnitude that users are used to from filling up vehicles with internal combustion engines. Exemplary details regarding DC charging and corresponding processes in a charging system and in a vehicle are described in DIN EN 61851, for example.
There is provision for vehicles to be enhanced for enabling higher charging speeds from the previously usual 400 V to at least 800 V, which can correspond approximately to a working range of 600 V to 950 V, sometimes even of 420 V to 980 V, on account of a voltage that is dependent on the state of charge and a certain variance in one configuration of the battery. A higher power can be transferred given the same current on account of the high voltage. In this way, the reduced charging period can be used to solve one of the main problems of electric vehicles.
In the event that charging columns use the mentioned high voltages of up to 1000 V and at the same time the corresponding charging columns are generally available in locations directly accessible for vehicles, there is the risk that the charging columns are damaged by vehicles or other mobile units, such as, for example, even animals etc., or the columns are damaged by other instances of vandalism. In this case, on account of the high voltages, it is not possible to ensure that no components of the charging columns are damaged, as a result of which there may possibly be a high risk for a user originating from the damaged charging columns.
In the prior art, concepts for blocking direct access to charging columns for vehicles are known.
Furthermore, various concepts for identifying collision and/or vandalism are known.
JP 2010-263666 A, which is incorporated by reference herein, for example, discloses a charging station, which comprises a circuit breaker, which breaks a circuit as soon as a collision is detected by collision detection sensors as an instance of collision acceleration.
DE 10 2011 076 183 A1, which is incorporated by reference herein, discloses an arrangement and a method for protecting an electrical connection against disturbances. To this end, a disturbance detector is provided which detects, for example, moisture on electrical contacts of a plug or on a surface on an induction plate, whereupon the charging process is interrupted or the process is continued with a reduced charging power.
US 2013/0193918 A, which is incorporated by reference herein, discloses providing a detector unit, using which a fault in the charging station, in the electric vehicle or in a connection between the charging station and the electric vehicle can be identified. In this case, the mentioned fault comprises incorrect positioning of the electric vehicle relative to the charging station, an incorrect position of the charging arm, a temperature outside of a desired scope or a current outside of a desired range.